ThePortForum.com

http://churchills-porthouse.com/
Greek Street, London - book in advance.

Bumped into this by pure chance whilst wandering through on Friday.
Went there yesterday evening for a very enjoyable set of tapas and port - it is being run by members of the Graham family as a semi-fun semi-marketing place.
Open only for 21 days in 2013 and 21 days in 2014, due to licensing, this pop-up is only around Nov-Feb.

Ports on offer:
White, Reserva, LBV, 10 yo, 20 yo, Gricha 2005, Vintage 1997, Vintage 2011.

link to the other thread on this

I rather liked the 20yr tawny, don't think i've ever had the 97 and would be interested to try the 2011 again (it showed quite well at BFT and did not seem to be in the "showy up-front-fruit" camp).

Only thing preventing me going is that prices seem so steep (£7 for a glass of 10YO at a producer-sponsored pop-up.....even if the price is written in a cutesy way!). I wonder if there are deals on flights or full bottles.